double type guard

spinn_machine/version/abstract_version.py

@@ -14,6 +14,7 @@
 from __future__ import annotations
 import logging
 from typing import Mapping, Optional, Sequence, Tuple, TYPE_CHECKING
+from typing_extensions import TypeGuard
 from spinn_utilities.abstract_base import AbstractBase, abstractmethod
 from spinn_utilities.log import FormatAdapter
 from spinn_utilities.config_holder import get_config_int_or_none
@@ -252,7 +253,8 @@ def get_potential_ethernet_chips(
         """
         raise NotImplementedError
 
-    def verify_size(self, width: Optional[int], height: Optional[int]):
+    def verify_size(self, width: Optional[int],
+                    height: Optional[int]) -> TypeGuard[int, int]:
         """
         Checks that the width and height are allowed for this version.
 

spinn_machine/virtual_machine.py

@@ -84,18 +84,6 @@ class _VirtualMachine(object):
 
     ORIGIN = "Virtual"
 
-    @overload
-    def __init__(
-            self, width: int, height: int,
-            validate: bool = True, n_cores: None = None):
-        ...
-
-    @overload
-    def __init__(
-            self, width: None = None, height: None = None,
-            validate: bool = True, n_cores: int = 0):
-        ...
-
     def __init__(
             self, width: Optional[int] = None, height: Optional[int] = None,
             validate: bool = True, n_cores: Optional[int] = None):